If the songs have lyrics, do they distract you? Do you prefer classical or movie soundtracks to inspire your writing? Or do you require silence when you write?
I'm all over the map, but generally I listen to music as I write. I have an iTunes playlist called "gooshy songs" that I listen to when I'm writing emotional scenes, but most of my choices depend on my mood.
Since I write historicals, I also like to listen to period appropriate music to get me in the mood. When writing a 1915-set romance, I found a youtube video of an Al Jolson recording, just the song I wanted my heroine and her sister to quote to each other when teasing about their respective love interests.
It's been fun.
So what about you? What do you do?